FORM Core Review

In This Review
Performance Tests | Firmness | Support & Sleeping Positions | Design | Materials | Comparisons | FAQs

At NapLab, we put each mattress to the test.

We test 10 different factors that impact the performance, comfort, and feel of the mattress. We then take the results of those tests and compare them to every mattress we’ve tested to date.

Check out the full performance table below to see how this mattress ranks:

Factor	FORM Core	Average
Overall Score	8.60	8.52
Price (Queen)	$1,399	$2,374 (Specialty only)
Cooling – Score	9.0	8.6
Sinkage – Depth	1.82″	2.25″
Sinkage – Feel	Minimal	Moderate
Motion Transfer – Score	8.4	8.2
Motion Transfer – Acceleration	8.55 m/s²	8.79 m/s²
Response Time – Score	9.1	8.8
Response Time – Mostly Recovered	0.2 sec.	0.4 sec.
Response Time – Fully Recovered	1.3 sec.	1.0 sec.
Bounce – Height	8.32″	8.68″
Bounce – Feel	Moderate	Moderate
Edge Support – Score	8.1	8.7
Edge Support – Sitting	3.75″	3.85″
Edge Support – Lying	Fair	Good
Sex – Score	8.1	8.2
Pressure Relief – Score	8.0	8.6
Comfort Layer Thickness	3.25″	4.35″
Mattress Thickness	9.00″	12.30″
Off-Gassing – Score	8.1	7.9
Off-Gassing – Smell	Strong	Strong
Off-Gassing – Days	7 days	8 days
Company – Score	10	8.8
Trial	365 nights	191 nights
Warranty	Lifetime	40% have lifetime warranties, average of other 60% of mattresses is 13 years

How is FORM Core Different?

The FORM Core is a 9.00″ specialty mattress with an overall performance level that is slightly better than average and a price tag that is significantly less than average. The end result is a value specialty mattress at a fraction of the cost of similar competitive brands.

Advantages

This mattress has better cooling performance, better motion isolation, and faster material responsiveness. The price is also a big advantage, coming in 41% below the average specialty mattress we’ve tested.

If you are specifically looking for that polymer gel grid, and don’t want to pay the premium price of Purple, the FORM Core could be a solid option.

Neutral Factors

Neutral factors for the FORM Core mattress include minimal sinkage and moderate levels of bounce. This mattress has a slight contour, which is good if you prefer a mattress that doesn’t hug you too closely. Instead, it creates more of a buoyant and floating feeling where the body lies more “on” top of the mattress as opposed to sinking down “in” the mattress.

Disadvantages

Disadvantages of the FORM Core mattress include worse pressure relief and worse edge support for both sitting and lying.

This mattress is only 9.0″ thick, which can be problematic for heavier weighted sleepers or those who are looking for exceptional pressure relief.

The FORM Core has excellent cooling. During our tests, I did not feel any significant level of heat retention around my body.

The better-than-average cooling performance is primarily driven by the gel pad. The gel pad is formed with a grid-like pattern, which creates sizable air pockets throughout the layer.

• Baseline Temperature – the temperature of the mattress before anyone lies on it
• Maximum Temperature (0 minute) – the temperature of the mattress after lying on it for 15 minutes
• Ending Temperature (5 minute) – the temperature of the mattress after being lied upon and having no one on it for 5 minutes

The air pockets mean there is less material that can easily absorb and retain heat. The cover is thin, non-quilted, and breathable. This cover helps to improve airflow and breathability for the mattress.

In our objective temperature tests, we measured a max surface level temperature of 90.3° F. This is 0.1° warmer than the average of 90.2° F, based on all of our tests to date.

After getting off the mattress, the temperature declined by 4.5 degrees from minutes 0 to 1, which is 0.3 degrees less cool than the average 0 to 1 minute decline of 4.8 degrees.

When we consider the combination of objective data, my subjective experiences, and an analysis of the materials, I’m confident in my view that cooling is excellent.

The FORM Core has minimal sinkage. During our tests, we measured a pressure point sinkage depth of 1.82″. This is 0.43″ less sinkage than the average sinkage depth of 2.25″, based on all of our tests to date.

The level of sinkage is documented in the image below.

The mattress creates only a slight body contouring hug. While there is a slight contour, it’s only for the heavier, bonier, and more protruding parts of the body (head, elbows, feet, butt).

In addition, the more restrained sinkage depth creates more of a floating feel where the body lies more “on” the mattress as opposed to sinking down “in” the mattress. The gel grid creates a more unique feel and is very similar to the feel of Purple mattresses that we’ve tested.

The FORM Core has a low level of motion transfer. During our tests, we measured a total acceleration range of 8.55 m/s². This is 3% less motion transfer than the average of 8.80 m/s².

The slightly lower-than-average motion transfer can be primarily attributed to the foam base layer.

While the gel grid is highly bouncy and responsive, it’s also relatively thin at just 1.5” thick. The bulk of this mattress is poly foam. That poly foam keeps bounce lower than average, which in turn keeps motion held to a reasonable level.

The level of motion transfer is also documented in the video below.

In our motion transfer chart, which visualizes our accelerometer data, we can see the highest motion peaks from 0 to 0.2 seconds. Motion declines notably thereafter, but still remains fairly steady until 0.8 seconds.

By 1.10 seconds, we’ve returned to near-zero levels of energy, which is 0.20 seconds longer than the average motion duration of 0.90 seconds.

Certainly, the motion duration and motion constancy from 0.2 to 0.8 seconds is less-than-great. Even so, motion intensity is also below average. All factors considered, this level of motion transfer is good, but not amazing either.

The FORM Core is a mixed bag for material responsiveness, with an extremely fast mostly recovered response time and a moderate fully recovered response time.

In our mostly recovered test, we measured a recovery speed of 0.2 seconds, which is 0.22 seconds faster than the average of 0.42 seconds, based on all of our tests to date.

In our fully recovered responsiveness test, we measured a recovery speed of 1.3 seconds, which is 0.28 seconds slower than the average of 1.02 seconds.

The level of responsiveness is documented in the video below.

This mattress is a tale of two material types. First, we have the gel pad, which is incredibly responsive, resilient, and springs back to shape effectively instantly.

However, some of the foam layers below the gel pad take a moment or two to fully recover to their original shapes after being compressed. These layers slow down the total responsiveness of the mattress.

To be fair, it’s still going to be plenty fast enough for most people and it is better than average, though it’s certainly not the fastest we’ve tested.

The FORM Core has a moderate level of bounce. During our tests, we measured a total bounce height of 8.32″. This is 0.35″ less bounce than the average of 8.67″, based on all of our tests to date.

The more restrained level of bounce is the product of the significant foam layers within the mattress.

While FORM Core does utilize a 1.5” gel pad, the majority of the materials are still poly foam. Poly foam simply doesn’t create significant bounce, especially when compared to the level of bounce created by coil and hybrid mattresses.

The level of bounce is also documented in the video below.

The more restrained bounce makes this mattress worse for sex performance, but it’s also the reason that motion transfer is fairly low.

The FORM Core has excellent sitting edge support and fair lying edge support.

In our sitting edge support test, we measured a sitting sinkage compression of 3.75″. This is 0.10″ less sitting sinkage than the average of 3.85″, based on all of our tests to date.

The level of edge support while seated is documented in the images below.

While lying directly on the edge of the mattress, I felt that the support was fair in all sleeping positions. Notably, this mattress is equipped with reinforced edge support.

That reinforcing foam running along the full perimeter is 3” wide along the left and right sides, 10” wide at the head and foot, and 1” tall. While it’s great to see reinforced support foam along the edge, the limited 1” thickness is just not thick enough to make a major impact for lying edge support.

The level of edge support while lying is documented in the images below.

In addition, the mattress has a dramatic downward curvature at the edges of the mattress.

This downward curvature, in combination with the thinner-than-average total height, easy squishiness of the gel pad, and limited edge support foam, creates the conditions for disappointing lying edge support.

The FORM Core has good sex performance. First, let’s talk about what the mattress does well. Both cooling and sitting edge support are excellent.

While lying edge support struggled, sitting edge support measured in at 3.75”, which is better than average. This helps to extend the usable surface area of the mattress for amorous activities.

Moving on with middling scores, we have pressure relief and noise, which were good, but also not amazing. We noted a little more noise due to the relative thinness of the mattress, which was able to bounce up and down more freely while under amorous pressure.

Sex Factor	Factor Weight	Score	Rating
Bounce	65%	7.7	Moderate
Edge Support	20%	9.1	Excellent
Noise	5%	8.0	Moderate
Pressure Relief	5%	8.0	Good
Cooling	5%	9.0	Excellent

Lastly, we need to talk about bounce, which we measured at 8.32”. This is less bounce than average. When it comes to sex, more bounce is almost always better than less.

This more restrained level of bounce makes the mattress more tiring and strenuous for amorous activities. Overall, sex performance is fine, but there is clearly room for improvement.

The FORM Core has a good level of pressure relief. During our tests, I felt no significant pressure points on my body. However, it was also clear that pressure relief did not rise to the excellent or outstanding level.

The mattress is equipped with 3.25″ of comfort material, which is 1.09″ less comfort material than the average comfort layer thickness of 4.34″, based on all of our tests to date.

In addition to the comfort layer being thinner than average, I’m also less-than-thrilled with the quality of the comfort materials. To be fair, the gel pad seems good and on par with Purple’s gel pad quality (which is the only other brand I’ve seen use this type of gel material).

That said, the foam quality leaves something to be desired. The foams just don’t look or feel especially great, both on the body and in-hand. In addition, in our foam density tests, we found the foam layers to be well south of what we ideally want to see.

Lastly, the mattress is only 9.0” tall (it’s supposed to be 10”, but the mattress we tested only measured 9.0”). Thinner mattresses often struggle to create ideal comfort and pressure relief, and that’s exactly what we experienced here as well.

All that said, and to be fair, it’s not bad, it’s just not great either.

In addition, you’ll want to note that this mattress has only a slight body contouring hug, minimal sinkage, and more of a floating feel. This feel isn’t good or bad, but it is a more specific and polarizing feel, one you’ll need to prefer in order to be comfortable on this mattress.

Lastly, in our objective pressure mapping tests, we measured a max PSI of 0.87. While this is within the 1.0 PSI threshold that I ideally want to see, it’s also higher than the average (0.76 PSI is the average max for lying on your back).

Pressure Relief (PSI)	Average	Maximum
Side Sleepers	0.11	0.52

Pressure Relief (PSI)	Average	Maximum
Back Sleepers	0.80	0.87

Pressure Relief (PSI)	Average	Maximum
Stomach Sleepers	0.08	0.44

When I consider our objective pressure mapping tests, material thickness, material quality, and my subjective experience on the mattress, I’m confident most sleepers will find the pressure relief to be good.

The FORM Core had a strong smell upon the initial unboxing. The mattress smelled for 7 days. This is 0.5 days shorter than the average smell duration of 7.5 days.

FORM mattresses come with a 365-night trial period and a lifetime warranty. Shipping and returns are both free.

Company Factor	Factor Weight	Score	Data
Returns	40%	10	$0
Trial Period	30%	10	365 nights
Warranty	20%	10	Lifetime
Shipping	10%	10	$0
Country of Origin	0%		USA

Comparing 117+ brands tested to date, the average trial period is 191 nights, 174 nights less than FORM offers. The FORM mattress is also backed by a lifetime warranty, which is a benefit only offered by 40% of mattresses that we’ve tested to date.

The FORM Core is only available in a single firmness option, which we rate as medium-firm. This is a rating of 6 out of 10, where 10 is the most firm.

Support on the FORM Core is good. During our tests, I felt well supported in all sleeping positions. That said, it’s also clear that support performance doesn’t rise to the excellent or outstanding level.

Support Factor	Data
Comfort Layer	3.25″
Support Layer	5.75″
Firmness	Medium-Firm
Body Contour	Slight
Zoned Support	No
Reinforced Edge	Yes

The mattress is equipped with a 5.75″ support layer. This is 2.20″ thinner than the average support layer thickness of 7.95″, based on all of our tests to date.

For a mattress to create ideal support, it needs to both fully support the body, maintaining a neutral spinal alignment, while also providing sufficient comfort and pressure relief.

With respect to support, the FORM Core does reasonably well, and yet, I am concerned that the limited 9.0” height simply won’t be thick enough for many sleepers, especially those who sleep on their side and / or those over 200 pounds.

In addition, while pressure relief was fine, it’s also far from amazing. The limited comfort layer simply left me less-than-impressed with its pressure relief.

Moving on, this mattress has a medium-firm feel, 6 out of 10 firmness. That firmness will work well for most sleepers.

Check out the table below to see the sleeper weights and sleeping positions that would be best suited for this mattress.

Sleeper Weight	Stomach Sleeper	Side Sleeper	Back Sleeper
Under 150 lbs.	Yes	Maybe	Yes
150-250 lbs.	Yes	Maybe	Yes
250-300 lbs.	Yes	Maybe	Yes

In all mattress tests, we make it a point to cut the mattress open and examine the material quality. In doing so, we found the gel pad looks and feels high quality, both on the body and in-hand.

However, the quality of the foam layers was less-than-great. The foam density levels were below the levels we hope to see (1.71 PCF for the comfort foam and 1.59 PCF for the support foam).

The more limited foam quality, in combination with the considerably thinner-than-average design, creates conditions that are less-than-great for longevity and durability, in my view.

Lastly, this mattress does not use any type of zoned support. Based on all of my tests to date, an analysis of the materials, and my subjective experiences, I’m confident that most sleepers will find support on the FORM Core to be good.

The FORM Core is a 9.00″ specialty mattress that comes in a single firmness option—Medium-Firm. It has a low-profile design, a thin cover, and a relatively lightweight total weight (just 72 lbs.)

Design Factor	Data
Type	Specialty
Thickness	9.00″
Cover Type	Thin
Weight	72 lbs.
Has Handles	No
Fiberglass-Free	Yes
Ships in a Box	Yes

Within the FORM collection, the FORM Core is the base level model below the Core Hybrid. For a more luxurious pick, FORM also offers the Prime collection—including the Prime and Prime X, for a gel grid over $2K for a queen mattress.

The FORM Core is 9.00″ thick and contains a combination of different foam types and a polymer grid gel pad. From top to bottom, here is a full list of the materials used in this mattress:

Layer Type	Thickness	Manufacturer’s Specs	Tested Specs
Thin Cover	0.50″	Not Available	Not Available
Gel Pad	1.50″	Not Available	52.4 PCF
Poly Foam	1.25″	Not Available	1.71 PCF
Support Foam	5.75″	Not Available	1.59 PCF

The FORM Core has a 0.50″ thin cover that is designed with integrated “cool on contact” material. When paired with the polymer gel grid, the cooling of this mattress was, indeed, excellent.

The comfort layer is 3.25″ thick, including the cover. Beneath the cover is a 1.5″ gel grid. The gel grid is wrapped by a poly foam perimeter, which is shown in the image below. This foam helps to improve edge support and give a bit of structure to the gel grid.

Below the gel grid is a 1.25″ poly foam that sits above the support layer. This combination of foam and gel pad provides comfort and transitional support as sleepers engage more deeply with the mattress.

The support layer is 5.75″ thick and made of a single layer of support foam. While I would have liked to have seen a denser foam used for the support layer, considering its value price tag and thinner profile, it’s not bad.

Product Evolution

FORM is a newer mattress brand that has developed a line of specialty mattresses that use a polymer gel grid (similar to the material Purple uses for their mattresses). FORM is the sister brand of Amerisleep, which has a longer history, being founded in 2010.

FORM launched their brand in 2026 with four mattresses—the Core (this review), Core Hybrid, Prime, and Prime Hybrid.

Other Mattresses to Consider

Not sure if the FORM Core is the right pick for you? Check out these three other top-rated specialty mattresses for alternatives you may want to consider.

Frequently Asked Questions

Still have questions? Check out some of the top FAQs on the FORM Core mattress below and get the answers you’re looking for.